Israeli government websites were down on Sunday, two days after the hacker group Anonymous had threatened to attack the government for its maritime blockade of the Gaza Strip.
Israel has however said that the websites were down because of a server malfunction.
The English websites of the Mossad intelligence service, and Israel Defense Forces (IDF) were still down late Sunday. The website of Mossad was under maintenance, while that of IDF was not accessible. The website of the Israel Security Agency, known as Shabak or Shin Bet, was also under maintenance.
"Israeli government websites crashed today because of a server malfunction, not as a result of a cyber attack," said Ofir Gendelman, a spokesman in the Israel Prime Minister's Office, in a Twitter message on Sunday.
Several Israeli government websites, including those of the IDF, Mossad and the Shin Bet internal security service were down on Sunday, according to reports in some newspapers in Israeli.
In a message on YouTube on Friday, Anonymous criticized the Israeli Navy's interception and boarding on Friday in international waters of two vessels - one Irish and the other Canadian - which were not carrying any weapons,.
"As the world has witnessed today your Navy soldiers boarded the vessels which were en-route to the Gaza Strip, attempting to break the illegal maritime security blockade placed by you to hurt the people of Gaza in the name of counter terrorism," Anonymous said in what it described as an open letter to the government of Israel.
Anonymous threatened to strike back again and again, if Israel continues blocking humanitarian vessels to Gaza. Anonymous MMV, the group that posted the video, has not taken credit so far for bringing down the websites in Israel.